Kaboul began his career at Auxerre and was a regular for the club by 2006. He won the Coupe de France in 2005, as well as having European football experience in the UEFA Cup. He was known to be the 'back bone' for Auxerre, due to his excellent tackling skills, good judgment and strength. He was also known to score a few key goals that clinched wins for Auxerre.[3]

Kaboul signed for Tottenham Hotspur on 5 July 2007, for an undisclosed fee believed to be around £8 million.[4] He quickly became a fans favourite, admired for his power and aggression on the pitch.[5] He played his first game for Tottenham in a friendly against St. Patrick's Athletic on 12 July. Kaboul made his Premier League debut, starting alongside Anthony Gardner, in the centre of defence in a 1–0 loss against Sunderland on the first day of the 2007–08 season. Kaboul then scored his first goal for Tottenham on 1 September against Fulham.[6] He scored again on his European debut for Tottenham, on 20 September, netting the first goal in a 6–1 win over Anorthosis.[7] On 1 October on the club's 125th anniversary, Kaboul scored the equalizer late in stoppage time against Aston Villa to pull Tottenham level at 4–4 and complete a remarkable comeback from 4–1 down.[8] After a period out of the team due to numerous errors,[citation needed] his comeback to the side away to Derby County on 8 February 2008, saw him score his fourth goal of the season.[9] He came on as an extra-time substitute as Spurs beat Chelsea in the 2008 Football League Cup Final. Overall Kaboul made 29 appearances for Tottenham in his initial spell at the club, and scored four goals.[10]

On 11 August 2008, Kaboul joined Portsmouth on a four year contract, for an undisclosed fee, believed to be around £6 million.[11][12] His first goal for Portsmouth came in the UEFA Cup against A.C. Milan on 27 November 2008.[13] His first league goal was an emphatic left footed strike into the top corner, on 12 April 2009 at home against West Bromwich Albion.[14] He scored his second league goal in a 4–1 loss to Arsenal on 22 August.[15]

In total, Kaboul made 50 appearances for Portsmouth, scoring five goals.[10]

On 30 January 2010, Tottenham Hotspur announced that Kaboul would be rejoining the club for an undisclosed fee, reported to be £9.5 million. Portsmouth would receive just £6.5 million of this owing to installments outstanding on the earlier transfer and to a sell-on clause.[12][16] Manager Harry Redknapp stated that the player was "much improved" from his original spell at White Hart Lane, and that Kaboul was a "late developer."[17]

On 5 May 2010, Kaboul was in the starting 11 against Manchester City playing right back. He was instrumental in the goal that brought Tottenham a 0–1 victory, whipping in a cross that the City goalkeeper could only palm into the path of Tottenham striker Peter Crouch. This victory guaranteed them fourth position in the Premiership and passage into the UEFA Champions League qualifiers for the first time in the club's history.[18] Kaboul scored the winner in the North London derby against Arsenal in a match which Spurs were 2–0 down at half-time. Kaboul continued his scoring form, volleying home 1–0 in a 3–0 victory against Werder Bremen in the Champions League. In the second game of the 2011–12 campaign he added his third goal since returning to Tottenham with a consolation goal in a 5–1 home loss to Manchester City. On 15 September 2014 it was announced that Kaboul would be Tottenham's permanent club captain.